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CVE-2026-68553 (GCVE-0-2026-68553)

Vulnerability from cvelistv5 – Published: 2026-08-19 20:37 – Updated: 2026-08-20 19:48
VLAI
Title
Coturn: Format String Injection via TURN USERNAME/REALM into hiredis Redis Command
Summary
Coturn is a free open source implementation of TURN and STUN Server. Prior to 4.13.0, an authenticated TURN user can place printf-style format specifiers in the STUN USERNAME or REALM attribute, which passes is_secure_string() validation and is embedded into Redis keys at nine call sites in src/apps/relay/ns_ioalib_engine_impl.c. send_message_to_redis() in src/apps/relay/hiredis_libevent2.c then passes the attacker-controlled key as the format argument to redisAsyncCommand() while supplying only one variadic value, causing hiredis redisvFormatCommand() to read past the va_list. Exploitation can crash the coturn process and terminate active TURN sessions or disclose stack memory into Redis. This issue is fixed in version 4.13.0.
Severity
7.1 (High)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:H
SSVC
Exploitation: poc Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-20 19:48 UTC
CWE
  • CWE-134 - Use of Externally-Controlled Format String
Assigner
References
Impacted products
Vendor Product Version CPE status
coturn coturn Affected: < 4.13.0
guessed Create a notification for this product.
Show details on NVD website
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